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Investment Securities - Schedule of available-for-sale securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Gain (Loss) on Securities [Line Items]
Unrealized gain (loss) on investment securities held at the end of the period	$ (14,799)	$ 1,602	$ 716
Investment securities	85,415	47,878
Seed Investments
Gain (Loss) on Securities [Line Items]
Net investment gain (loss) of consolidated investment products	(3,407)	(401)	160
Long-Term Cash Awards
Gain (Loss) on Securities [Line Items]
Net investment gain (loss) of consolidated investment products	(13,198)	2,716	0
Other Investments
Gain (Loss) on Securities [Line Items]
Net investment gain (loss) of consolidated investment products	332	(559)	145
Consolidated Entity Excluding Variable Interest Entities (VIE)
Gain (Loss) on Securities [Line Items]
Net investment gain (loss) of consolidated investment products	(16,273)	$ 1,756	$ 305
Long-Term Cash Awards
Gain (Loss) on Securities [Line Items]
Investment securities	$ 63,300

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Amount of realized and unrealized gain (loss) on investment.

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